IDEC MicroSmart - Manual (Page 407)

24: A NALOG I/O C ONTROL
« FC4A M ICRO S MART U SER ’ S M ANUAL » 24-21
Changing Analog Output While CPU is Stopped
When using the FC4A-K2C1 analog output module, the analog output value can be changed while the CPU module is
stopped. To change the analog output value, store a required output value to the memory addresses allocated to the analog
output data.
Example: Memory Allocation of Ladder Refresh Type Analog Output Module FC4A-K2C1
STPA instruction when FC4A-K2C1 is mounted on slot 4
Ladder Diagram
Note: The above ladder diagram is only an example and should be modified as required.
Precautions for Programming ANST Macro
When using the ANST macro, do not make a branch from the ladder line of the ANST macro.
Delete the branch from the ANST macro, and start another line by inserting a LOD instruction.
Memory Address
(data address used for STPA)
Data Size
(bytes)
R/W Parameter
+20 2 R/W
Analog Output Data
CH0
+22 2 R/W CH1
M8120 is the initialize pulse special internal
relay.
MOV stores output values at the OFF state.
When the CPU stops, STPA updates the analog
output value of the analog output module.
M8120
REP
2
S1 –
0
D1 R
D1400
MOV(I)
DATA
D1400
SLOT
4
STATUS
D1500
BYTE
4
ADDRESS
20 WRITE
STPA(I)
M8120
NO.1
J8AT1
ANST
Q1
Incorrect
M8120
NO.1
J8AT1
ANST
Q1 M8120
Correct